Days after LA voters approved a law that limits the number of pot dispensaries in the city, HempCon, America’s biggest medical marijuana convention, kicked off in downtown Los Angeles.

The event includes exhibits from local medical marijuana dispensaries, as well presentations by attorneys and activists such as Richard Eastman, who helped start the first pot dispensary in LA in the mid 1990s.

Defense attorney Freddy Sayegh, Hempcon’s keynote speaker, said the event was scheduled months ago, before LA voters approved Measure D to limit the number of pot dispensaries in the city.

He thinks Measure D will have a negative effect.

“You’re going to see the growth of underground sales of narcotics and trafficking,” Sayegh said.